Cord blood cytokine levels in neonates born to mothers with prolonged premature rupture of membranes and its relationship with morbidity and mortality.

The purpose of this study was to determine cord blood cytokine levels and their relationship with morbidity and mortality in neonates with prolonged, premature rupture of membranes (PPROM). Forty two premature neonates of 29-35 weeks gestational age with PPROM exceeding 24 hours were considered as the PPROM group and simultaneously, 41 premature neonates without PPROM were considered as the control group. All the neonates were admitted to the Neonatology Unit for further evaluation of subsequent complications such as early neonatal sepsis, pneumonia, intraventicular haemorrhage (IVH), respiratory distress syndrome (RDS), necrotizing enterocolitis (NEC) and chronic lung disease (CLD). Cord blood and mothers' blood samples were obtained during delivery in both groups and tested for IL-6, IL-8 and TNF-alpha levels. Twenty one percent of patients with PPROM had histological chorioamnionitis. The risk for developing early neonatal sepsis increased significantly in neonates whose mothers had histological chorioamnionitis (p < 0.05). There was a statistically significant relationship between PPROM and risk of developing NEC (p < 0.05); no significant increase was seen as regards early neonatal sepsis, IVH, RDS, pneumonia, or BPD. The mean IL-8 levels in cord blood and mothers' serum were significantly higher in the PPROM group (p < 0.001, p< 0.005). In addition, IL-6 levels found in mothers' serum were significantly higher than those found in the control group (p < 0.01). However, levels in cord blood were similar (p > 0.05). TNF-alpha levels were similar in both groups (p > 0.05). Neonates who developed NEC had higher IL-8 levels in their cord blood when compared to those without NEC (p < 0.05). In conclusion, the presence of PPROM increases the risk of chorioamnionitis. In addition, PPROM increases the risk of NEC, and patients who developed NEC had significantly higher cord blood IL-8 values. We may conclude that patients with PPROM and higher IL-8 levels in cord blood might be considered as at possible risk of NEC.